It is known that distribution switchboards for distributing electric power to a plurality of electrical devices, such as circuit breakers or other switching devices, can use a system of mutually parallel bus bars.
Each one of the bars can be electrically connected to a corresponding phase of the electric power supply mains, wherein the connection between the bus bars and the devices installed into the switchboard can be provided by means of adapter conductors, such as for example laminae, which can be shaped appropriately according to the type of device.
Bus bars, according to the functions that they perform in the practical application, have a few basic characteristics; for example, bus bars can have a simple and functional constructive structure, which can allow flexibility in assembly and coupling to other conducting or insulating elements.
For example, it is known to use flat bars with a solid rectangular transverse cross-section.
It is also known to use bus bars whose transverse cross-sections can be shaped to facilitate coupling to other bars or to supporting and/or insulation elements; these elements can be used to fix the bus bars to supporting structures and to assist them in withstanding the electrodynamic stresses.
For example, shaped bus bars are known, for example, with a body having, on an upper side, two C-shaped slots for receiving therein a corresponding fixing means. The lower side of these bus bars can have a central portion, for example, a portion extending over a corresponding portion between the two upper C-slots, which can be constituted by a large thickness portion of conducting material.
It is known that bus bars can heat significantly when current is flowing through the bus bar and the dissipation of electric energy in form of heat can limit the current conducting capability of the bus bars.
Furthermore, considering two known bus bars placed adjacent to each other, relevant electromagnetic forces can be generated between such bus bars during the current flowing therethrough. These electromagnetic forces can jeopardize the electrical conducting performances of the bus bars. For example, this situation can occur when a fault current is generated through the bus bars, such as a current due to a short-circuit. The generated electromagnetic forces, for example, can limit the rated short-time current (Icw) which the bus bars can bear.
The generated electromagnetic forces can also imply the use of a plurality of large dimensioned insulating supporting elements for the bus bars.